1. Field of the Invention
The invention relates to a wiring, a thin film transistor, a thin film transistor panel, and methods for manufacturing the same.
2. Description of the Related Art
In general, wirings or electrodes including chrome (Cr), aluminum (Al), molybdenum (Mo), or an alloy thereof are mainly used in semiconductor devices or liquid crystal display devices. For microfabrication of the semiconductor devices, due to high integration and a fast operating speed, copper (Cu) which has a lower electric resistance and has a higher resistance to electromigration and stress migration compared to aluminum, has been used for wirings or electrodes in semiconductor devices.
Even in the field of display devices represented by liquid crystal display devices and the like, low-resistance wirings are required due to the increase in resolution and display area, and the integration of devices including sensors and driver circuits, which may be integrated in the display devices. Therefore, gate or data wirings made of copper, or gate, drain and source electrodes of a thin film transistor (“TFT”), which are also made of copper, are applied to display devices.
However, when copper is used for wirings or electrodes, the diffusion of copper into adjacent circuit elements or a semiconductor layer of a TFT may degrade characteristics of pixel elements or TFTs. Therefore, it is required to prevent metal atoms, for example, copper atoms, contained in wirings or electrodes from being spread around and diffused into adjacent elements or layers.